It has been estimated that 60-90% of all human cancers are caused by exogenous agents, principally chemicals that humans are exposed to in food, water and air, Cancer (as well as other diseases) are usually by mutagenic events, which can be induced by a variety of mechanisms, including by cellular processing and DNA lesions (or adducts) formed from either endogenous or exogenous agents (chemicals). This proposal describes the second (Ventura, CA, March 3 - 8, 2002) and (2004) Gorden Research Conferences (GRC) on Mutagenesis and Carcinogenesis (M&C). These conferences will bring together experts in various aspects of DNA adduct-induced mutagenesis. Sessions will address three fundamental areas. [1] Mutagenic mechanisms, including adduct structure and conformation, adduct mutagenesis, and lesion bypass DNA polymerases. [2] Mutagenesis avoidance mechanisms, including adduct DNA repair, cell cycle arrest and apoptosis. [3] The relationship between mutagenesis and carcinogenesis. The breadth of topics will attract a diverse group of scientists with common interests in cellular mutagenic mechanisms, mutation avoidance mechanisms and the relationship between mutagenesis and carcinogenesis. Leading scientists in the field will present and evaluate the latest research at the frontiers of mutagenesis and carcinogenesis.